Auxiliary device for lathes



Oct. 12, 1954 BECHLER AUXILIARY DEVICE FOR LATHES 2 Sheets-Sheet 1 Filed Oct. 16, 1951 M; mm mm 8 1 I & FG G mwww w 9 wwm Q a w k S a Q Q 8 x Q TN IL Oct. 12, 1954 A. BECHLER AUXILIARY DEVICE FOR LATHES 2 Sheets-Sheet 2 Filed Oct. 16, 1951 Patented Oct. 12, 1954 UNITED STATES ATENT OFFICE Claims priority, application Switzerland October 26, 1950 2 Claims.

This invention relates to lathes and more especially to the toolboxes of slicing lathes.

It is an object of this invention to provide a revolving tool box fixed in position axially and rotatable about an axis parallel to the turning axis and supporting a plurality of tool-holder spindles which are movable in axial direction, at least one of these spindles being arranged to be revolved by means of power transmitting elements provided for this purpose.

In the tool box according to this invention the several tool-holders are arranged in parallel on the corners of a hypothetical polygon centered in the axis of revolution of the box. The revolving box consists of at least two coaxial parts fixed to one another, at least one of them is formed with a cavity in which certain power transmitting elements are housed. The revolving movement of the tool box takes place in at least one bearing, the supporting face of which has a larger diameter than the circle surrounding the tool-holder spindles.

This tool box thus distingushes clearly over the tool boxes of slicing lathes hitherto known, for instance the star-shaped boxes which must be mounted on a slide or carriage to advance and return the tool relative to the work and which do not carry rotary tools. They also distinguish over known tool boxes carrying a toolholder pivoted for angular movement to allow interchanging of tools and in which not more than three tools, rotary or stationary, can be mounted.

Means for driving rotary tool-holders are known, in which a driving shaft arranged coaxially to the tool-holder pivot drives power-transmitting elements accommodated in a cavity of the tool-holder. In certain turning operations it is advantageous to be able to rotate not only the Work, but also the tool, for instance in screwing, however the mechanisms designed for this purpose were too complicated to enable the operator to partly dismantle them for an interchange of tools which is desirable in the case of certain tools such as screw cutters, drills etc. Apart therefrom in tools of different sizes as a rule the shanks are not of uniform size and shape.

In a preferred form of the device according to this invention each tool spindle is formed with an axial groove, into which projects a driving pin or the'like fixed on a driving gear which, being fixed in axial direction, has the same diameter as a fulcrum pin fixed axially in the bearing plate, of every non-rotative spindle. In this device the cylindrical sections of all the spindles are of uniform diameter and screws are provided near the front ends of the bearings, which can be adjusted to enter into the axial groove of the non-rotary spindles, so that in every pair of bearings a rotary spindle can be replaced by a non-rotary one and every gear can serve equally as a trunnion of a non-rotary spindle or a means of connection between the driving gear and the gear mounted on a rotary spindle.

With the mechanism according to this invention all different operations (boring, screwing,

grooving etc.) can freely be gone through, owing mainly to the fact that every rotary tool-holder spindle can be set rotating by the central gear (sun gear) either directly (and then in opposite sense) or by means of an intermediate gear which, in order not to complicate the design of the tool-holder, turns on a non-rotary spindle, for which it serves as a guide in its advance and return movement relative to the work.

In the drawings afiixed to this specification and forming part thereof, an embodiment of this invention is illustrated diagrammatically by way of example.

In the drawings Fig. 1 is an elevational view of an axial partsection of the device on the line II in Fig. 2.

Fig. 2 is a cross-section on the line II-II in Fig. 1.

Referring to the drawings, I is a support arranged for horizontal adjustment on a guide rail 2 mounted on the lathe structure. 3 is the head-stock, t is a workpiece held in position by the, chuck 5.

The support I is formed integral with a rear bearing 6 supporting the rear portion I of a frame whose forward portion 8 can revolve in the coaxial front bearing 9. The rear part I is secured in its bearing 6 against axial displacement by means of locking rings It containing screws H. The supporting faces of the part a and bearing 8 are conicaland this bearing can be adjusted axially on the support l by means of a bolt or bolts ll. This arrangement allows the bearing 9 to be removed altogether if the forward part 8 of the tool box. shall be removed after the three screws l2 have been loosened which fix the two sections 1 and 8 of the revolution body together in the correct position, which is that position, in which the two sections are coaxial and bearings I4 in a flange 83 of the rear section I register exactly with borings E5 in the front wall of the bowl-shaped body 3. To this end each screw I2 is formed with a cylindrical shaft I6 which fits in borlngs provided in the two sections of the tool box.

The rear section is composed of the flange l3 and the hollow shaft I in which rotates a driving shaft 18 carrying a pulley 19 at its outer end and a sun gear 20 at the other end, fixed by means of a screw 2 I.

All borings it of the flange 13 and all the borings iii are of uniform diameter. The common axes of the diifercnt pairs of borings are parallel to the axis of rotation of the tool box and the lathe and are arranged in the corners of a regular polygon (hexagon in the case here shown), whose center is located on the axis of rotation of the tool box. Every boring M can house a journal 22 or a gear 23. Those sections of the journals 22 or the gears 23 which are seated in these borings and are held therein by means of locking rings 24 with screws 25, have the same diameter as the borings it, while their inner diameters are the same as those of the borings l and as the outer diameter of the six spindle shafts 28a, 25b, 26c, 26d, 26a and 2B which are mounted in the six pairs of borings 14, I5.

In the tool-holder spindle 28a is fixed by means of a set screw 27 the cylindrical shaft of a drill 28. The other spindles which .are intended to hold other kinds of tools, carry clamping chucks or inner fastening cones. The spindle 26 is driven by the gear 23 with the aid of a pin 29 projecting into the axial groove '38 of this spindle.

The spindle Zed cannot rotate, because one of the six screws 3! which extend radially to the revolution body and the borings 15 in the front wall of the bowl-shaped. frame section 8, projects into the groove 36 of this spindle, while the screw 3| of the spindle 26a has been adjusted to leave the spindle free to revolve.

The spindles can be rotary or stationary and are interchangeable. A non-rotary spindle can be rotated by simply adjusting the screw 3i and mounting on thespindle a gear meshing with the central gear 26. If thespindle is intended to revolve in a direction opposite to that of the driving shaft 18, it should mesh directly with the central wheel. In the other case a gear 23 mounted on another spindle and in mesh with the central gear may be inserted in the drive. This other spindle may be a rotary spindle rotating in opposite sense than the driving shaft and will be provided with a projecting pin 28, or it may be stationary, being coupled by means of such pin and its gear will then merely serve to transmit the driving movement. Non-rotary spindles which carry no movement-transmitting gear, may turn in a journal 22 (see spindle 26:1).

The device is also provided with means for indexing the tool-holder or revolution body in a single sense of revolution. For the sake of simplicity it has been assumed that the indexin means comprise handles 32 fixed on the forward section of the tool box and a spring-actuated lever 33 pivoted on "the support I and having a tooth 3d entering one of a plurality of indentations 35 in the flange 1 3 (Fig. 2).

Besides this, means are also provided for advancing and returning the spindle occupying the operative position. For the sake of simplicity it is here assumed that a hand lever 36 pivoted to the support acts on'th'e heads of the screw bolts '51 mounted in the spindles 26a-f in the axial direction, being blocked by counter-nuts so as to be able to regulate individually the stroke of the different spindles. The movement of the lever is limited by a check 30, the spindles are returned by coil springs 40 surrounding them and resting against the front wall 8 and against stop-rings M fixed on the spindle by means of set screws 42.

If the device hereabove described is mounted in an automatic lathe, the indexing of the tool box and the axial shifting of the spindles into working position may be efiected automatically, for instance by suitable cam means well known in automatic lathes.

I wish it to be understood that I do not desire to be limited to the details shown in the drawings and described in this specification, for obvicus modifications will occur to a person skilled in the art.

I claim:

1. Turret for automatic lathes comprising in combination, a base plate having two ends, a

shaft hearing at one end and a guide surface parallel to the longitudinal axis of said shaft bearing on the other end of said plate, a bearing member engaging said guide surface, a bearing opening in said bearing member coaxial to said shaft bearing, means for locking said bearing member to said base plate, a tool box including a hollow shaft, a disc flange at one end of said hollow shaft, said hollow shaft being rotatably supported in said shaft bearing and secured against axial movement, said tool box including a cup shaped part having a substantially flat bottom portion and an outside surface portion rotatable in said bearing opening, the opening of said cup shaped part being closed by said disc flange to form a completely closed gear box, said flange and said bottom portion each having a plurality of bores arranged in circles coaxial with said hollow shaft, the bores in the flange being respectively coaxial to the bores in the bottom portion, the bores in said bottom portion having all the same diameter, the bores in said flange having the same diameter which is greater than the diameter of the bores in the bottom portion, interchangeable bushing members and pi-nions individually having identical tubular portions and being individually mounted in the bores of said flange, said pinions being located within the gear box, removable setting means for preventing axial movement of said bushing members and of said pinions in said flange, cylindrical tool carriers individually longitudinally slidably supported in the bores of said bottom portion and in said bushing members or in said pinions, and being removable from said bushing members and pinions upon separation of said cup shaped part from said flange, each tool carrier having on its outside a longitudinal groove the length of which is greater than the length of said cup shaped part plus the thick-nessof the flange; means individually adjustable in the bottom portion of said cup shaped part and adapted to individually engage the grooves in said carriers for preventing rotation of the carrier whose groove is engaged, a means fixed to each of said pinions and engaging the groove of the tool carrier extending through the respective pinion, providing a driving connection between the pinion and the tool carrier, a drive shaft rotatably mounted in, and protruding at both ends from said hollow shaft, a drive means connected to the end of said drive shaft which is distal with respect to said flange and a solar pinion fixed to the end of said drive shaft which is proximal to said flange, said solar pinion meshing with the pinions mounted on said flange, means for indexing the tool box, and means for individually longitudinally reciprocating said tool carriers.

2. Turret for automatic lathes comprising in combination, an axially immovable tool box rotatable around an axis parallel to the working axis of the lathe, a plurality of cylindrical tool carriers arranged in said box parallel to and in a circle concentric to the rotation axis of the tool box. said carriers having the same diameter and being axially movable, bushings for supporting a plurality of said tool carriers in said box, each of said carriers having a longitudinal groove, a driving gear in said box, at least one pinion having a tubular extension and forming a bushing for supporting one of said tool carriers in said box, said pinion meshing with said driving gear, a pin extending from said pinion into the groove of the tool carrier supported by the pinion, and screws at the working end of said box adapted to be individually entered into the grooves of predetermined tool carriers to prevent rotation thereof.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,268,386 Potter June 4, 1918 1,810,227 Shea June 16, 1931 FOREIGN PATENTS Number Country Date 621,807 Great Britain Apr. 20, 1949 

